Question

An example of a precipitation titration reaction is the Mohr
method, which is used to find the concentration of halide ions in
solution (particularly Cl- and Br-). First, the sample to be
analyzed is titrated with a AgNO3 solution, which results in the
precipitation of a white silver solid AgCl. Because it is difficult
to tell when all the halide ion has reacted with the silver ion, a
small amount of an indicator ion, {CrO4}^{2-}, is added to the
reaction. Because Ag2CrO4 is more soluble than AgCl, the \rm
Ag_2CrO_4 precipitates out only after all of the \rm Cl^- ion has
precipitated out as \rm AgCl. Thus, as soon as all of the \rm Cl^-
ion has reacted, the \rm Ag_2CrO_4 precipitation begins, marking
the equivalence point of the reaction by forming a rust-colored
precipitate.

You enter the lab to analyze the chip filtrate for \rm Cl^-. First,
you prepare a solution of silver nitrate, \rm AgNO_3, and titrate
it against 0.500 \rm g of \rm KCl using the Mohr method. You find
that it takes 62.9 mL of \rm AgNO_3 titrant to fully reach the
equivalence point of the reaction.
You then use the same silver nitrate solution to analyze the chip
filtrate in a Mohr reaction, finding that the solution yields a
rusty brown precipitate when 49.6 mL of titrant is added.

Part A
If the sample of chips used to make the filtrate weighed 82.0 g,
how much \rm NaCl
is present in one serving (115 g) of chips?